Engine starter



Nov., 6, 193 J. A. CHARTER ENGINE STARTER Filed June 8, 1929 z; 34 J5 J;

iatented Nov. 6, 1934 UNITED STATES ENGINE STARTER James A. Charter,Chicago, 111., assignor to Charter Drive, Inc., Chicago, 111., acorporation of Illinois Application June 8, 1929, Serial No. 369,392

11 Claims.

This invention relates to engine starters and particularly to startersfor internal combustion engines of automobiles and the like.

Certain of the functional characteristics of my present invention bearrelation to starters of the type disclosed in my Patents Nos. 1,554,-623 and 1,682,368 and my co-pending application Serial No. 343,718,filed March 1, 1929, in that my present invention contemplates theprovision 13 of a starter in which a driving pinion is adapted to bemoved into engagement with the fly-wheel or driving gear of the enginein response to relative movement between a helical spring and a trackerwhich is positioned between the convolutions of said spring. The presentinvention however relates to certain advantageous structural featuresand novel arrangement of cooperating parts which are not disclosed in myaforementioned application and patents.

One of the objects of my present invention is to provide a startermechanism of the type set forth above with an improved structuralarrangement for securing one extremity of the helical spring to acompanion rotative element of the starter as for example the drivingmember or pinion. I

A still further object of my present invention is to rigidly connect theextremity of the spring with one of the rotative elements in such amanmar as to enable said spring to be readily attached or detached withrespect to said rotative element.

More specifically, my invention contemplates the provision of a recessor slot within the rotative element such as the driving pinion whichwill enable the extremity of either a right or a left hand spring to beconveniently connected with or detached from said rotary element.

Still another object of my present invention is 40 to provide incombination with the above mentioned helical spring a tracker member ofimproved practical construction which may be readily associated with ordetached from the spiral way presented between the convolutions of saidspring and thereby .facilitate .the ease with which the parts comprisingthe starter mechanism may be assembled or disassembled for purposes ofrepair or replacement.

In addition to the above mentioned advantageous characteristics myinvention contemplates the provision of a tracker means or member bf theabove mentioned type which is adapted to project inwardly between theconvolutions of the spiral spring and thereby obviate the necessity ofproviding a tracker member or pro- Figure 2 is a central verticalsectional view taken longitudinally of the device shown in Figure 1;

Figure 3 is a plan view of the device shown in Figure 1 after thedriving member or pinion has been moved into operative association with7 the driven gear;

Figure 4 discloses a starter mechanism of the type shown in Figures 1 to3 inclusive, the same being provided with helical springs of modifiedconstruction; and

Figure 5 is a view similar to Figure 4 disclosing the driving member orpinion in its advanced position, operatively associated with the drivenengine gear.

Referring now to the drawing more in detail 35 wherein like numeralshave been employed to designate similar parts throughout the. variousfigures, it will be observed that I have illustrated a practicalembodiment of the invention in Figures 1 to 3 inclusive which includes astarter shaft 10 suitably connected with and driven by a starting motorindicated by dotted lines and designated generally by the numeral 12. Adriving member or pinion 14 is 'rotatably mounted upon the shaft 10 andthis member includes a gear portion 16 and a helical section 18 formedintegral therewith. Obviously, the gear 16 and the section 18 might beconstructed of two or more elements as distinguished from the integralarrangement shown in the drawing. The cylindrical section 18 is formedwith a peripheral T-shaped recess or slot 20 which is adapted to receivea hook portion 22 of a helical spring 24.

This helical spring 24 encircles the drive shaft 10 and the convolutionsthereof are spaced so as to present a helical way 26. The hook extremity22 of the spring is adapted to be received within the T-shaped slot 20as clearly shown in Figure 1 while the opposite extremity 28 of the 1101 ion and spring will be longitudinally spring is adapted to engage anabutment or stop when said spring or driving pinion or unit 14 occupiesthe retracted position shown in Figures 1' and 2.

This abutment or stop 30 is secured to or formed upon the annularsection 32 of an actuating -means designated generally by the nurneral34. The annular section of this actuating section 84 is apertured to bereceived by the outer extremity of the drive shaft 10 and is secured tosaid drive shaft in any suitable manner as by means of a set screw 36.Extending laterally of and in the particular instance formed integralwith the annular section 32 is an arm 38 which is provided at its outerextremity with a depending lug or tracker 40. The arm 38 is positionedso as to clear the periphery of the coiled spring 24 and the trackerprojects downwardly within the helical way 26 presented between thespring convolutions.

1 From the foregoing it will be clear that if the driving pinion or unit14 together with the spring 24 occupy the retracted position shown inFigures 1 and 2 and sudden rotation is imparted to theshaft 10 in aclockwise direction as viewed from the left of said figures, thepinmoved to the right in response to the rotative movement of thetracker 40 within the helical way 26. In other words, the suddenrotation imparted by the actuating means 34 will 'cause said means torotate independently of the coiled spring 24 and hence a relativerotative movement takes place between the tracker 40 and the spring soas to cause said spring to be moved axially to the right. As the partsare thus moved to the right,.the teeth of the pinion proper 16 arecarried into mesh with a driven gear 42. This gear 42 in many instancescomprises a portion of the fly-wheel structure. When the pinion has beenadvanced to the position shown in Figure 3 into operative associationwith the driven gear 42, the tracker 40 will be carried into engagementwith the hook portion or extremity 28 of the spring. The resilientcharacteristic of the spring at this instant serves to take up any shockwhich might result from the sudden en-.

gagement of the tracker with the spring extremity 28. Thus, after thetracker 40 engages the spring extremity 28 a positive driving connectionis established between the drive shaft 10 and the driving pinion, so asto impart rotation to the driven gear 42. When the gear 42 has beenrotated for a sufficient period to cause the engine with which it isassociated to start, the peripheral speed of said gear will eventuallyexceed the peripheral speed of the driving unit or pinion and under suchconditions the pinion will be rotated in a clockwise direction as viewedfrom the right of Figures 1 to 3 inclusive independently of the shaft 10and its associated actuating means 34. The rotation of the pinionobviously causes similar rotation of the coiled spring 24, with theresult that the relative movement between the spring and the tracker 40causes the spring and pinion as a driving unit to be retracted, therebywithdrawing the pinion from operative engagement with the driven gear42. The \retracting movement of the spring is interrupted by theengagement of the spring extremity 28 with the abutment 36 carried bythe annular member 32. The resiliency of the spring serves to take upthe shock experienced by the engagement of the extremity 28 with theabutment 30 or in other words, a cushioning efiect is experienced whichmaterially reduces the shocks which would otherwise be experienced uponthe sudden retraction and stopping of the spring and pinion. In someinstances there is a tendency for the spring and pinion to rotativelyrebound in response to the engagement of the extremity 28 with theabutment 30 and this rebound has a. tendency to impart relative rotationbetween the tracker and the spring, thereby causing a slight forwardmovement to the right, Figures 1 and 2, of the pinion. Forward movementof the pinion in response to the rebounding or kick back effect isavoided by the presence of a resilient ring or abutment 44 which iscarried by the shaft 10. This resilient abutment 44 does not in itselfform the subject matter of the present invention but is described indetail and claimed in my above mentioned co-pending application. It willsuffice to say that this ring is split so as to enable the same toexpand sumciently so as to annularly project beyond the periphery of theshaft 10. Obviously the resiliency of the abutment 44 is readilyovercome when rotation is imparted to the shaft 10 by the startingmotor, but said resiliency is sufficient to prevent the pinion ordriving unit 14 from being inadvertently moved toward the drivengear inresponse to the 'kick back or rebounding action of the spring or inresponse to other vibrations to which the parts are normally subjected.

In Figures 4 and 5 I have disclosed a starter simulating the starterjust described but having certain different structural characteristics.Thus, it will be noted that the starter shown in Figures 4 and 5 isprovided with the usual shaft 10 and the driving unit 14 comprising thepinion proper and the annular section 18. Encircling the shaft 10between the section 18 and an annular member or collar 32a is a pair ofco-operating coiled springs denoted generally by the numerals 24a and24b. One extremity of the spring 24!) is provided with a hook 22b whichis mounted in the T-slot 20 of the section 18 similarly to the mannerdescribed in connection with the structure shown in Figures 1 to 3inclusive. The opposite extremity of the spring 24b is provided with ahook portion 46 which is adapted, when the springs 24a and 24b occupythe position shown in Figure 5, to interlock with a companion hookportion 48 at one extremity of the spring 24a. The opposite extremity ofthe spring 241: is provided with a hook 220 which is securedfwithin aT-shaped slot 20a. It will be observed that the spiral way 26a presentedbetween the convolutions of the coil 20a is equal in width to the-widthof vthe hook 46 of the spring 24b. Likewise, the spiral or helical way26b, Figure 5, presented between the convolutions of the spring 24b isequal in width to the hook portion 48 of the spring 24a. Thus one springis adapted to be screwed into and out of association with the other.When said springs have been screwed together as shown in Figure 4, thehook portion 46 of the spring 24!; is moved into engagement with anabutment or projection 50 carried by the shaft 10 and the driving memberor pinion 16 is in its retracted position out of operative associationwith the driven gear 42.

Assume that the parts occupy the position shown in Figure 4 and rotationis suddenly imparted to the shaft 10 in a clockwise direction as viewedfrom the left of Figure 4. This sudden rotation will cause an initialindependent k to cause the spring 24b and actuating means afiixed enginewith which it is vided without departing from the 25 -ing the necessityof providing rotation between the springs 24a and 24b so as the drivingpinion connected thereto to be moved axially toward the driven gear 42.when the pinion has been moved to the position shown in Figure 5, thehook portions 46 and 48 of the springs will become retracted, therebysetting up a positive driving connection between the annular section 32aand the driving pinion 16. When the driven gear 42 has been rotatedsufliciently to start the associated, and the peripheral speed thereofis in excess of the peripheral speed of the driving pinion, said pinionwill be rotated independently of the shaft 10, thereby causing thehelical spring 24b to be screwed within the spring 24a, thereby carryingthe driving pinion to the position shown in Figure 4. The engagement ofthe hook portion 46 with the abutment 50 will arrest the axial movementof the parts. Obviously other types of interlocking springs as well asother means for arresting the inward movement of the spring connectedwith the driving pinion may be prospirit and scope of my invention.

From the foregoing it will be apparent that my invention providesseveral distinct movements and advantages over types of engine starterswhich have heretofore been employed. Some of these advantages reside inthe provision of a tracker such as the tracker 40 shown in Figures 1 to3 inclusive which projects from a point externally of the spring intothe helical way of said spring. By having this arrangement it is notnecessary to provide the shaft 10 with a radial tracker device and theassembly and disassembly of the parts is greatly facilitated. The simpleand unique manner in which I secure the extremity of the helical springwithin one of the driving parts presents a structure which is verypractical and which provides a very positive connecting means. By havingthe hook portion 22 of the spring inserted within the T-shaped slot 20,it is impossible by the 5 application of a rotative pull upon thespring,

to dislodge said spring from the section 18. The fact that the sectionof the hook 22 which lies within the circumferential portion of theT-shaped slot 20 cannot be bent with respect to the remaining portion ofthe spring positively prevents the spring from being pulled out of saidslot. The T arrangement of the slot 20 enables either left or righthanded springs to be connectedto the section 18, therebyprecluddifierent parts to accommodate diflerently coiled springs.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. In an engine starting device of the class described, a drive shaftunit, an engine driving member on said unit for both longitudinalmovement and rotary movement, said member being adapted, when properlypositioned, to operatively engage an engine part to be driven, a

coiled spring encircling said drive shaft unit and amxed to said enginedriving member, and an to said drive shaft unit, said actuating meansincluding a projection and supporting means therefor adapted to extendover the coiled spring and connected with said unit at a point locatedexternally of the coiled spring, said projection being positionedbetween the convolutions of said spring and adapted in response torelative movement between the spring and the projection, to cause theengine driving member to be carried into operative association with theengine part to be driven.

2. In an engine starting device of the class described, a drive shaftunit, an engine driving member on said unit for both longitudinalmovement and rotary movement, said member being adapted, when properlypositioned, to operatively engage an engine part to be driven, a coiledspring encircling said drive shaft unit and afilxed to said enginedriving member, a projection rotatable with said drive shaft unit andmovable between the convolutions of said spring, a member extendingaxially over said coiled spring and providing a support for saidprojection. said member being rotatable as a unit with said drive shaftunit, a stop engageable with said projection to limit the axial movementof the driving member in one direction, and a stop adapted to be engagedby thd free extremity of the coiled spring to limit axial movement ofsaid spring in the opposite direction.

3. In an engine starting device of the class described, a drive shaftunit, an engine driving member on said unit for both longitudinalmovement and rotary movement, said member being adapted, when properlypositioned, to operatively engage an engine partto be driven, a coiledspring encircling said drive shaft unit and affixed at one extremity tosaid engine driving member, a projection rotatable with said drive shaftunit and positioned between the ,convolutions of said spring, a memberextending axially over said coiled spring and providing a support forsaid projection, said member being rotatable as a unit with said driveshaft unit, a

stop for engaging-said-projection to limit the longitudinal movement ofthe spring and driving member in one direction, and a stop rotatable'with said'drive shaft unit for engaging the free extremity of the coiledspring to limit the longitudinal movement thereof in the oppositeshiftable longitudinally thereof, said spring being formed at oneextremity with a hooked portion, said hooked portion including a sectionbent in-a circumferential direction, a recess-provided in one of thestarter elements for receiving said hooked portion to afiix said springextremity thereto against relative axial displacement in eitherdirectory, and driving means carried by the unit andproiecting withinthe coil convolutions. a

5. In an engine starting device of the class described, a drive shaftunit, an engine driving member for both longitudinal movement and rotarymovement, a coiled spring encircling said shaft, one extremity of saidcoiled spring having a hooked portion, said hooked portion including asection bent in a circumferential direction, a recess being provided insaid engine driving unit for receiving the hooked portion of said springto thereby secure said unit and spring against relative axialdisplacement in either direction, and means positioned between theconvolutions of said spring for efiecting longitudinal movement of thespring with respect unit.

to said drive shaft 6. In an engine starting device of the classdescribed, a drive shaft unit, an engine driving member on said unit forboth longitudinal movement and rotary movement, a coiled spring foroperatively connecting the drive shaft unit with the engine drivingmember, one extremity of said coiled spring being provided with alaterally extending portion, a T-shaped recess being provided in one ofthe elements associated therewith for receiving the laterally extendingportion of said spring.

7. In an engine starting device of the class described, a drive shaftunit, an engine driving member on said unit for both longitudinalmovement and rotary movement, said member being adapted, when properlypositioned, to operatively engage an engine part to be driven, a coiledspring encircling said drive shaft unit, a member on said drive shaftunit extending into the spring convolutions, a peripheral portion of oneof said elements associated with said spring being provided with arecess having an axially extending portion and a circumferential portionextending angularly with respect to said axially extending portion, oneextremity of said coiled spring being formed in accordance with theshape of the recess and adapted to be received by said recess forsecuring said extremity in proper position.

8. In an engine starting device of the class described, a drive shaftunit, an engine driving member on said unit for both longitudinalmovement and rotary movement, said member being adapted, when properlypositioned, to operatively engage an engine part to be driven, a coilspring encircling said drive sh ft and affixed to said engine drivingmember, and actuating means -aflixed to said drive shaft unit, saidmeans being anchored at a point spaced from the convolutions of saidspring and adapted to extend over said spring and having a portionpositioned between the convolutions of said spring and adapted, inresponse to relative movement between it and said spring, to cause theengine,

drivingmember to be carried into operative association with the enginepart to be driven.

9 In an engine starting device of the class described, a drive shaftunit, an engine driving member on said unit for both longitudinalmovement and rotary movement, said member being adapted, when properlypositioned, to operatively engage, an engine part to be driven, a coiledsprii-ig encircling said drive shaft t and afllxed to said enginedriving member, an actuating means afiixed to said drive shaft unit,said actuating means including a projection supported from a pointexternally of the coiled spring, said projection being positionedbetween the convolutions of said spring and adapted in response torelative movement between the spring and the projection, to cause theengine driving member to be carried into operative association with theengine part to be driven, and a stop movable with the drive shaft unitfor engaging the free end of the coiled spring when the engine drivingmember has been shifted away from the engine part to be driven.

10. In an engine starting device, a drive shaft unit, an engine drivingmember on said unit adapted for both longitudinal movement thereof androtary movement therewith, said member being adapted when properlypositioned to operatively engagean engine part to be driven, andconnecting means including a coiled spring operatively associated withsaid drive shaft unit, a peripheral portion of one of said elementsassociated with said spring being provided with a recess having anaxially extending portion and a circumferential portion extendingangularly with respect to said axially extending portion, one end ofsaid coiled spring being formed in accordance with the shape of therecess and adapted to be received by said recess for securing saidextremity against rotative displacement in at least one direction andalso against axial displacement with respect tothe part with which saidspring is connected. I

11. In an engine starting device, a drive shaft unit, an engine drivingmember on said unit adapted for both longitudinal movement thereof androtary movement therewith, said member being adapted when properlypositioned to operatively engage an engine part to be driven, andconnecting means including a coiled spring operatively associated withsaid drive shaft unit, a perip eral portion of one of said elementsassociated with said spring being provided with a recess having anaxially extending portion and a circumferential portion extendingangularly with respect to said axially extending portion, one end ofsaid coiled spring being formed with a hook portion adapted to bereceived by said recess for securing said extremity aga nst rotativedisplacement in at least one direction and also against axialdisplacement with respect to the part with which said extremity isconnected.

JAMES A. CHARTER.

